In the event of chronic kidney failure, various methods for the extra-corporeal treatment or cleansing of the blood are used to remove substances which are normally eliminated in the urine and for the purpose of therapeutic dehydration. In haemodialysis, the patient's blood is cleansed outside the body in a dialyzer. The dialyzer has a blood chamber and a dialysis-fluid chamber, which chambers are separated by a semi-permeable membrane. During the treatment, the patient's blood flows through the blood chamber, with dialysis fluid flowing through the dialysis-fluid chamber of the dialyzer to cleanse the blood of substances which are normally eliminated in the urine.
Whereas in hemodialysis (HD), the transport of the substances of lower molecular weight through the membrane of the dialyzer is determined in essence by the differences in concentration between the dialysis fluid and the blood (diffusion), in hemofiltration (HF), substances dissolved in the plasma, and particularly substances of higher molecular weight, are removed effectively by a high flow of liquid through the membrane of the dialyzer (convection). In hemofiltration the dialyser acts as a filter. A combination of the two methods is called hemodiafiltration (HDF).
In the extra-corporeal treatment of blood, such as hemodialysis for example, the following problems arise. During the dialysis, it is essentially only the patients' blood which is cleansed but not the cellular and intra-cellular compartments. Because the transport of the toxins dissolved in water into the blood takes place only very slowly, better results are obtained from a dialysis treatment extending over quite a long period of time than from a short dialysis. Because of the effective cleansing of the blood and the poor cleansing of the cellular and intra-cellular compartments, high concentration gradients arise. What therefore occurs immediately after the dialysis is a balancing of the concentrations of the toxins between the compartments and the blood, an occurrence which is referred to as a rebound. The rebound places a considerable stress on the patient's circulation. In certain cases, the rebound may even result in circulatory failure after dialysis. A further problem arises from the fact that the dialysis treatment has to be carried out in a sitting or lying position, because the patient's radius of action is restricted by the dialysis machine. Physical immobility however causes an inhibition of blood flow to the peripheral parts of the body, and particularly the legs, for which reason the blood is less well cleansed in these parts.
In the specialized field of dialysis, it is widely known that regular sporting activity by the patient has a beneficial effect on the dialysis treatment (Nephron 42: 311-316 (1986) Exercise Training Reduces Coronary Risk and Effectively Rehabilitates Hemodialysis Patients, Andrew P. Goldberg et al.).
It is also known that the efficiency of dialysis treatment can be significantly increased if the patient indulges in active physical activity during the dialysis treatment. The so-called rebound effects can also be reduced in this way. It is known that physical activity by the patient during the dialysis treatment results in improved blood circulation in the body, which means that the flow of blood is better through areas in which it is only weak, by which means the cleansing of the blood is improved. What is seen with physical activity during the dialysis is not only a slight rise in pulse rate and blood pressure but also improved metabolic exchange between the compartments and an increase in clearance, which is equivalent to dialysis treatment of longer duration. What is also seen is a reduction in the rebound of urea, creatinine and potassium (Nephron 43: 87-92 (1986), Effects of Exercise Training during Hemodialyses, Patricia L. Painter et al.; Nephrol Dial Transplant (1999) 14: 2927-2931, The effect of exercise during haemodialysis on solute removal, Chiew H. Kong et al.).
Also known as measures which stimulate the circulation and encourage blood flow are massages particularly of the patient's legs, although these are found to be labor-intensive and cost-intensive. Also, the results from massages are difficult to repeat.
The studies of the effect of sporting activity on the results of dialysis treatments were carried out on patients whose physical fitness was sufficiently good. However, because of the high average age of dialysis patients, which is approximately 67 years, the physical fitness of many such patients is no longer adequate for them to themselves actively perform sporting exercises during the dialysis treatment. Attention must also be paid to the fact that, when there are movements by the patient, the venous and/or the arterial needle may accidentally be disconnected during the dialysis. Therefore, any sporting activity by the dialysis patient during dialysis treatment requires closer monitoring, in which case the requirements which the technical safety precautions for quickly detecting the disconnection of a needle need to meet have to be made more stringent, which likewise involves higher costs.
In the field of sports medicine, it is known for the fitness of sportsmen and athletes to be increased by what is termed electrical muscle stimulation, also referred to as EMS. In this, the targeted electrical stimulation of the muscles is used not only for training but also for warming up, relaxing and accelerated regeneration. It is also known for electrical muscle stimulation (EMS) to be used for therapeutic measures.
US 2005/0131489 A1 for example describes the use of electrical muscle stimulation for preventing venous thromboses in immobile patients, such as in intensive care units, for example. An arrangement for muscle stimulation for the same application is also known from WO 03/063960 A2.
The object underlying the invention is to provide a medical blood-treating apparatus which allows blood to be treated extra-corporeally with greater efficiency. A further object of the invention is to specify a method for treating blood extra-corporeally with greater efficiency. It is also an object of the invention to provide an arrangement for the extra-corporeal treatment of blood for use with an arrangement for electrical muscle stimulation, and an arrangement for electrical muscle stimulation for use with an arrangement for the extra-corporeal treatment of blood, with which arrangements the efficiency of the extra-corporeal treatment of the blood can be increased.